Hearth for boiler fluidised bed

摘要

The hearth of a fluidised bed for a boiler has a wall (1) enclosing a central zone (6) and a fluidising grid (2). When the boiler is operating at low power the level of the fluidised bed is low (13) and at high power the bed level is high (14). - The hearth is equipped with a heat exchanger with tubes (7,8) which extend vertically between the lower and higher levels of the fluidised bed. The injectors for combustion air are mounted above the higher level near to the side wall and directed towards the central zone of the hearth.